Concentrations of serum constituents in cold-stressed calves from heifers fed inadequate protein and(or) energy

A study with neonatal calves was conducted to determine the effects of maternal crude protein (CP) and(or) metabolizable energy (ME) malnutrition, cold stress (0 or 21 degrees C), and age on concentrations of selected serum constituents. For each of 2 yr, 60 artificially bred Angus heifers were assigned randomly to a 2 x 2 factorial nutritional plan 150 d before predicted parturition. The diets provided each heifer with either .32 or .96 kg/d of CP and 8.7 or 12.6 Mcal/d of ME. Blood samples were obtained from heifers at parturition and from their calves at birth and at 12, 24, 36, 48, and 72 h of age. Sera were analyzed for concentrations of blood urea nitrogen (BUN), creatinine (Creat), iron, total protein (TProt), alkaline phosphatase (AlkPhos), total bilirubin (TBil), and cholesterol (Chol). Mean correlations of these constituents in calf sera between 12-h adjacency intervals were high, but those between longer times (48 or 60 h) were low. Simple correlations of serum constituents between cows and calves at birth were low except for BUN (r = .578 and .295 for yr 1 and 2, respectively). There were significant main treatment effects for maternal CP consumption on BUN levels, for environmental temperature on BUN, Creat, and TBil levels, and for years on BUN, Creat, iron, and AlkPhos levels in calves. Significant polynomial relationships were found over hours of age for all variables. Blood urea N decreased in normal calves but remained relatively constant at a low level in deficient calves. Year x hour of age interactions occurred for iron, TProt, AlkPhos, TBil, and Chol. Protein x year x hour of age interactions were found for iron and Chol. These results suggest that random sampling times are not useful for decision making during the first 72 h after birth. Consideration must be given to multiple samples taken at specific calf ages, to environmental temperatures, and to maternal protein nutritional levels when interpreting calf blood sera data.     

Comparison of the commercial agar-gel immunodiffusion test and radioimmunoprecipitation assay for detection of antibodies to bovine leukemia virus

In a double-blind study, the commercial agar-gel immunodiffusion test (AGID) was compared with a radioimmunoprecipitation assay (RIA) performed with glycoprotein (gp) antigen for detection of antibodies to bovine leukemia virus. Of 240 sera tested, 115 were from adult cows and 125 were from precolostral calves. Most adult animals were tested within 1 week of parturition. Sera from 74 cattle were positive and sera from 166 cattle were negative by gp RIA. Sensitivity of the AGID, compared with the gp RIA, was 85.1% when the test was read at 48 hours and was 94.6% when read at 72 hours. Specificity increased from 92.2% at 48 hours to 96.4% at 72 hours. Reading the AGID again at 72 hours also clarified most reactions that were questionable at 48 hours due to a haze around the test serum well. Of 3 RIA-positive precolostral calf sera, 2 were AGID-negative and 1 had a questionable reaction by the AGID at 48 hours. Of 5 RIA-positive sera that were AGID-negative at 48 hours, 2 were precolostral calves and 3 were cows tested at parturition. Of 166 RIA-negative reactions, none was falsely positive by the AGID at 48 or at 72 hours.     

Studies on the persistence of the organotin fungicide fentin acetate (triphenyltin acetate) in the soil and on surfaces exposed to light

The results of a study into the persistence of triphenyltin (=fentin) acetate in soil are presented. The fungicide is degraded biologically 50% being decomposed in 140 days. The photochemical degradation of fentin acetate into inorganic tin via diphenyltin and monophenyltin compounds also is demonstrated. The leaching of fentin acetate in soil and its effect on soil nitrification is discussed.     

Metabolism of bromhexine in pig hepatocyte cultures

The metabolism of bromhexine [N-cyclohexyl-N-methyl-2-(2-amino-3,5-di-bromo-benzyl)-amine] was studied using pig hepatocyte cultures and LC/MS/MS techniques. Phase I 'single-step' reactions, i.e. hydroxylation and demethylation occurred the fastest whereas the formation of hydroxylated/demethylated and aminal hydroxylated metabolites, which can be considered as multiple-step reactions, occurred more slowly. Phase II conjugates were detected for all hydroxylated metabolites. The glucuronides of the hydroxylated/demethylated components tended to accumulate. In addition to metabolites known to be formed in vivo, three unknown components related to bromhexine were detected. Two of these metabolites accumulated during incubation. Based on the fragmentation patterns, a possible molecular structure is proposed for these components.     

Modulation of the cytokine responses in equine macrophages following TACE-inhibition

The detrimental effects of the pro-inflammatory cytokine TNF-alpha during equine acute abdominal disease are well known. Its pivotal role in many human diseases has led to various in-depth studies regarding its release mechanism, in particular by TNF-alpha converting enzyme (TACE). In this study we investigated the inhibitory effect of a TACE-inhibitor on cytokine release (TNF-alpha, IL-1alpha and IL-6) in three different cell models, including U937 cells, a recently established equine macrophage cell line, known as eCAS, and primary equine PBMC. The aim was to show the similarity of TNF-alpha release through the TACE mechanism in human and equine cells after stimulation with LPS. Results indicate that, by using a TACE-inhibitor, TNF-alpha, IL-1alpha and IL-6 release can be reduced in both equine cell models and achieved comparable results in the human U937 cells. These results suggest that equine TNF-alpha, like its human homologue, is released from its membrane-bound position by TACE.     

Benzimidazole drugs and modulation of biotransformation enzymes

Benzimidazole drugs (e.g., anthelmintics albendazole, fenbendazole, oxfenbendazole, thiabendazole, mebendazole; inhibitors of proton pump omeprazole, lansoprasole, pantoprasole) represent substances used in both human and veterinary medicine; however, from the point of view of induction and inhibition of biotransformation enzymes, research has been carried out mainly due to the initiative of human pharmacologists. The purpose of the present review is to inform about inductive and inhibitive effects of benzimidazole drugs in man, animals and cell cultures. Pharmacological and toxicological consequences of modulation of biotransformation enzymes are discussed and the significance of studies in the field of modulation of biotransformation enzymes in food-producing animals is explained. Since the modulating effect of benzimidazoles strongly varies depending on structure of the individual substances, the particular attention is paid to structure-modulation relationships.     

Biological approaches for control of root pathogens of strawberry

ABSTRACT Soil fumigation with methyl bromide plus chloropicrin is used as a preplant treatment to control a broad range of pathogens in high-value annual crop production systems. In California, fumigation is used on approximately 10,125 ha of strawberry production to control pathogens ranging from Verticillium dahliae to root pruning pathogens such as Pythium, Rhizoctonia, or Cylindrocarpon spp. In addition to pathogen control, fumigation also causes an enhanced growth response of the plant and reduces weed pressure. The development of successful, long-term cost effective biocontrol strategies most likely will require the development of an integrated systems approach that incorporates diverse aspects of the crop production system. Although application of single microbial inoculants may provide some level of control for specific production problems, it will be a challenge to provide the broad spectrum of activity needed in production fields.